By Dan Williams
JERUSALEM (Reuters) - Israel has emerged from the past few days of fighting with Palestinians in Gaza more confident that its advanced missile shield and civil defenses can perform well in any war with Iran.
"In a sense, this was a mini-drill" for Iran, an Israeli official said on Tuesday after an Egyptian-brokered truce took hold, leaving 25 dead in the Gaza Strip and three people wounded in Israel.
"There are significant differences, of course, but the basic principles regarding the 'day after' scenarios are similar," the official said, alluding to Iran's threat to respond to any "pre-emptive strike" on its nuclear facilities by firing ballistic missiles at Israel.
Employing a similar doctrine of pre-emption against Palestinians, Israel killed two senior militants in a Gaza air strike on Friday, accusing them of planning a major attack on its citizens through the territory of neighboring Egypt.
That southern Israel weathered the ensuing scores of short-range rockets from Gaza, with sirens summoning around a million citizens to cover and the Iron Dome aerial shield providing extra protection, was savored - warily - by Israeli defense officials.
"The Israeli home front has shown once more that it can deal with the challenges," the armed forces' commander, Lieutenant-General Benny Gantz, told reporters.
Though he described the cumulative threat from surrounding armies and guerrillas as "significant and abundant", Gantz said: "I am convinced that our enemies understand the balance we have between a comfortable defense capability and our offensive capabilities, which we will use as required."
While Iron Dome is deployed against rockets from Gaza, Israel's answer to the bigger, ballistic missiles of Iran and Syria is Arrow II, an interceptor that works in a similar way but at far higher altitudes.
Israeli officials said Iron Dome shot down some three in four of the Palestinian rockets fired in recent days. Developers of the Arrow II, which has so far proved itself only in trials, boast a shoot-down rate for that system of some 90 percent.
Uzi Rubin, a veteran of the Arrow program, cautioned, however, against relying too far on such defenses as Iranian missiles, if not intercepted, could wreak far more damage than Gazan rockets, many of which are improvised from drainage pipes.
"We are talking about 750-kg (1,650-lb) warheads, enough to level a city block," Rubin said, noting there would be a greater impact if Iran's allies on Israel's borders -- Syria, Lebanon's Hezbollah guerrillas, and Palestinian militants -- joined in.
Yet some Israeli experts see that axis bending to new domestic political pressures, notably after the popular Arab revolts of the past year, which may reduce the extent to which Tehran can count on their support in any conflict with Israel.
Indeed, Israeli Defense Minister Ehud Barak has recently predicted that "maybe not even 500" of Israel's civilians would die in any counter-attack after a strike on Iran.
Gaza's governing Hamas movement stayed out of the four days of fighting waged by other militants -- a reflection, perhaps, of the powerful Islamist group's placing of domestic interests over any desire by Tehran to bleed Israel by proxy. Hamas's ties with long-time sponsors Iran and Syria have weakened this year.
Sanguine assessments by Israeli defense officials are at odds, however, with disclosures by an opposition lawmaker last month that, despite a government-sponsored fortification drive, almost one in four citizens lacked access to shelters.
Budgetary problems no doubt contributed to the lags in construction, and the economic damage of any conflict with Iran is a factor that those who counsel against over-confidence in defensive systems have highlighted.
Rubin noted that while the flare-up with the lightly armed Palestinians in Gaza had disrupted life and business activity only in Israel's southern periphery, Iran's missiles were easily capable of striking its main industrial hubs -- the Tel Aviv conurbation and Haifa port in the north.
"There would be a total economic paralysis," he said.
If it is planning to attack Iran, which denies seeking the bomb while preaching the Jewish state's destruction, Israel must contend with unprecedented tactical hurdles and the disapproval of the United States -- underwriter of Arrow II and Iron Dome.
Israel would also depend on Washington's grants for the two projects to bear the lopsided cost of each interception -- between $25,000 and $80,000 for Iron Dome, and $2 million and $3 million for Arrow.
Though Israel is widely assumed to have its own atomic arsenal, Prime Minister Benjamin Netanyahu dubs Iran a mortal threat and described the recent Gaza rockets as a harbinger.
"These terrorist attacks, by Islamic Jihad for example, demonstrate the scale of the danger that will be wrought if, God forbid, a nuclear Iran stands behind them," he said on Monday.
(Additional reporting by Maayan Lubell; Writing by Dan Williams; Editing by Alastair Macdonald)